A comparison of anthropometric and training characteristics of Ironman triathletes and Triple Iron ultra-triathletes

We examined differences in anthropometry and training between 64 Triple Iron ultra-triathletes competing over 11.4 km swimming, 540 km cycling, and 126.6 km running, and 71 Ironman triathletes competing over 3.8 km swimming, 180 km cycling, and 42.2 km running. The association of anthropometry and training with race time was investigated using multiple linear regression analysis. The Triple Iron ultra-triathletes were smaller (P < 0.05), had shorter limbs (P < 0.05), a higher body mass index (P < 0.05), and larger limb circumferences (P < 0.01) than the Ironman triathletes. The Triple Iron ultra-triathletes trained for more hours (P < 0.01) and covered more kilometres (P < 0.01), but speed in running during training was slower compared with the Ironman triathletes (P < 0.01). For Triple Iron ultra-triathletes, percent body fat (P = 0.022), training volume per week (P < 0.0001), and weekly kilometres in both cycling (P < 0.0001) and running (P < 0.0001) were related to race time. For Ironman triathletes, percent body fat (P < 0.0001), circumference of upper arm (P = 0.006), and speed in cycling training (P = 0.012) were associated with total race time. We conclude that both Triple Iron ultra-triathletes and Ironman triathletes appeared to profit from low body fat. Triple Iron ultra-triathletes relied more on training volume in cycling and running, whereas speed in cycling training was related to race time in Ironman triathletes.     

Finite element modelling and experimental study of oblique soccer ball bounce

In this study, we develop a finite element model to examine the oblique soccer ball bounce. A careful simulation of the interaction between the ball membrane and air pressure in the ball makes the model more realistic than analytical models, and helps us to conduct an accurate study on the effect of different parameters on a bouncing ball. This finite element model includes a surface-based fluid cavity to model the mechanical response between the ball carcass and the internal air of the ball. An experimental set-up was devised to study the bounce of the ball in game-relevant impact conditions. Ball speed, angle, and spin were measured before and after the bounce, as well as ball deformation and the forces during the impact. The finite element model has been validated with three different sets of data, and the results demonstrate that the finite element model reported here is a valuable tool for the study of ball bounce. After validation of the model, the effect of the friction coefficient on soccer ball bounce was studied numerically. Simulation results show that increasing the friction coefficient may result in reversal of the horizontal impact force.     

Golf styles and centre of pressure patterns when using different golf clubs

When using a driver, the centre of pressure of a golfer shows a pattern that is characteristic of one of two distinct swing styles: the "front foot" style or the "reverse" style. The aim of this study was to establish whether these two swing styles are also evident when using other clubs, and if so, to determine whether golfers use the same swing style when using different clubs. Forty-six professional, amateur, and recreational golfers performed swings to hit a ball into a net placed 3 m away. Ten swings were performed for each of the driver, 3-iron, and 7-iron while standing on two force plates. The position of the golfer's centre of pressure parallel with the line of shot and relative to the feet was quantified at eight swing events that were identified from 200-Hz video. Cluster analysis confirmed that the front foot and reverse styles were evident in all three clubs, and most of the golfers (96%) used the same swing style for all three clubs. Golfers that used the reverse swing positioned their centre of pressure nearer to their toes at ball contact compared with golfers that used the front foot swing.     

Differentiating experts' anticipatory skills in beach volleyball

In this study, we examined how perceptual-motor expertise and watching experience contribute to anticipating the outcome of opponents' attacking actions in beach volleyball. To this end, we invited 8 expert beach volleyball players, 8 expert coaches, 8 expert referees, and 8 control participants with no beach volleyball experience to watch videos of attack sequences that were occluded at three different times and to predict the outcome of these situations. Results showed that expert players and coaches (who were both perceptual-motor experts) outperformed the expert referees (who were watching experts but did not have the same motor expertise) and the control group in the latest occlusion condition (i.e., at spiker-ball contact). This finding suggests that perceptual-motor expertise may contribute to successful action anticipation in beach volleyball.     

Stress responses during aerobic exercise in relation to motivational dominance and state

We examined the hypothesis that congruence between motivational dominance and state results in optimal psychological responses and performance during exercise. Twenty participants (10 telic dominant and 10 paratelic dominant) rated their stress at 5 min intervals as they cycled on an ergometer at gas exchange threshold for 30 min in both telic and paratelic state manipulated conditions. Participants then performed a test to exhaustion at a resistance equivalent to 110% of VO(2max). The hypothesized interaction between condition and dominance was significant for internal tension stress, as paratelic dominants were more stressed than telic dominants when exercising in the telic state and telic dominants were more stressed than paratelic dominants when exercising in the paratelic state. Similarly, the condition × dominance interaction for internal stress discrepancy was significant, as paratelic dominants reported greater internal stress discrepancy exercising in the telic compared with the paratelic state. Findings are discussed in relation to the application of reversal theory for understanding stress responses during aerobic exercise.     

美国非本土博士与本土博士的工作角色与薪酬比较———对美国1999—2008年博士学位获得者的调查

对那些参与了美国国家科学基金会博士学位获得者调查（SDR）的非美国本土的博士学位获得者完成学业后的工资、工资增长和就业单位等方面进行了调查,调查结果显示,非美国本土的劳动者在1999年的平均年薪比美国本土的同行低,但是10年后的2008年,非美国本土的劳动者的工资超过了那些美国本土的同行.分析还发现,非美国本土与美国本土的博士10年间工资增长存在差异.差异可能是由于学科专业和市场需求等因素导致的.     

贝多芬的吻

我16岁时,由于与音乐教师发生分歧,处于某种危机之中。后来,一个著名的钢琴家艾米尔·冯·萨尔——李斯特最后一个活着的弟子,来到布达佩斯,要求我为他弹奏。他专心地听我弹了巴赫的C大调《Toccata》,并要求听更多的曲子。我全身心投入弹奏贝多芬的《Pathetique》奏鸣曲和舒曼的作品《Papillons》之中。最后,艾米尔·冯·萨尔起身,在我的前额上吻了一下。＂我的孩子,＂他说,＂在像你这么大时,我成了李斯特的学生。     

给伊丽莎白一支红玫瑰

伊丽莎白捧着一束雏菊走到院子里。 “美丽的鲜花献给……给……噢,我看我永远都说不好了!”她叫着,把雏菊扔到地上。     

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